Chelsea's Brazilian star Oscar says the bitter memory of a shock semi-final defeat at the Club World Cup two years ago makes him even more determined the lift the trophy this year.

The attacking midfielder was on the receiving end of one of the biggest upsets in the history of the intercontinental championships when Brazil's Internacional lost 2-0 to Democratic Republic of Congo minnows TP Mazembe in the UAE in 2010.

It meant Internacional missed out on a final against Italian giants Inter Milan, who were then coached by Oscar's current coach at Chelsea, Rafael Benitez.

"It was unbelievable at the time, and what made it worse was the fact that we knew we had the quality to win that game and then beat Inter as our team was very strong," the 21-year-old midfielder said.

"It really was a major disappointment. We were all surprised because we knew our team was superior to theirs.

"Mazembe scored to go 1-0 up, and while we did everything in our power to try and secure a draw, it wasn't possible," added Oscar, who has featured in all but one of Chelsea's English Premier League matches this season.

Inter went on to defeat TP Mazembe 3-0 while Internacional had to settle for third place with a 4-2 win over Seongnam Ilhwa Chunma, a match Oscar sat out.

"I didn't take part in the second game, but I remember it well because we were all feeling so down after losing to Mazembe," he said.

"All we were thinking about was meeting Inter, who had already qualified, in the final, and we were confident we could beat them."

Oscar said the experience meant he would be completely focused on beating Mexican side Monterrey in Yokohama today, and would not be distracted by the prospect of a glamour final against Brazilian giants Corinthians.

"I have learned from past experience with Internacional that you have to take one game at a time," he said.

"If we get to the final, which I hope we do, it will be great for me personally to play against a Brazilian side, but I will be doing my best to help Chelsea win the game."

Chelsea come into the tournament on the back of a win at Sunderland, which ended a poor run, including two draws and a defeat in Benitez's first three games in charge.

They became the first Champions League holders to exit the competition at the group stage last week, giving added incentive to their first foray into the club showpiece. "I think we, as players, are all taking this competition very seriously," added Oscar, who was signed in the summer. "It's a very important trophy for every club and for the career of every individual."

This article appeared in the South China Morning Post print edition as Oscar eager to make amends for bitter 2010 defeat